British Journal of Urology (1972). 44, 9-14

ERRORS AND PITFALLS IN THE MANAGEMENT OF ACUTE URINARY OBSTRUCTION COMPLICATED BY URAMIA WITH

SPECIAL REFERENCE TO STONE1

By E. PROCA Associate Professor of Urological Surgery, Patirluri Hospital, Biicliarest

UREMIC conditions are far from unusual in a urological department and often both the diagnostic and therapeutic problems they present are not easily solved.

During the last 11 years (1960-1970) we have treated 1,155 cases with renal failure from a total number of 31,671 patients admitted to our hospital (Fig. 1) .

In nearly half of these patients (461 cases) the urremia was related to acute tubular necrosis and will not be analysed in this paper.

In the other 654 patients (who had blood urea levels greater than 70 mg. per 100 ml. when admitted) the uramia was related to mechanical obstruction of the urinary passages (Fig. 2).

Compared with the reversible renal failure accompanying acute tubular necrosis or the relentlessly progressive course of nephrosclerosis, obstructive urremia has some definite features:

1. I t occurs late in the evolution of urinary disease. 2. Its development is characterised by fluctuations associated with either acute temporary

obstruction or exacerbations of pyelonephritis. 3. The urinary output is usually preserved. 4. Surgery plays a definite part in the management. 5. Sudden anuria may be the first clinical symptom of a long, silent history of urinary tract

In this paper the discussion will be restricted to the errors and pitfalls we have encountered

obstruction.

in the management of calculous anuria and bilateral obstructive nephrolithiasis.

Calculous Amria.-In this group there were 80 patients. All of them were admitted with complete anuria and various degrees of uramia: 51 (63 per cent) patients had blood urea levels less than 200 mg. per 100 ml. and were considered to be in the so-called clinical " tolerance " phase of urzmia, while 29 patients (37 per cent) had blood urea levels within the range of 200-680 mg. per 100 m1.-with a mean value of 348 mg. per 100 m1.-and presented severe symptoms of uramic intoxication.

In all our cases the anuria was exclusively due to mechanical obstruction of the urinary tract: 20 patients had bilateral stones either in the renal pelvis (15 cases) or in the ureters ( 5 cases) while 60 patients had a single functioning kidney with calculous obstruction: in 22 patients the contralateral kidney had been previously removed (in 19 for stones, in 3 for tuberculosis) and in the other 38 patients the other kidney was functionless.

Only 11 of these 38 patients were aware that they had a non-functioning kidney. In the other 27 patients, it was anuria that revealed for the first time the existence of a silently destroyed contralateral kidney (25 cases) or its congenital absence (2 cases) (Fig. 3).

We have never encountered the so-called calculous reflex anuria and consequently very much doubt its existence.

Emergency relief of the obstruction either surgically or by means of an indwelling ureteral catheter is obviously required.

1 Read at the Twenty-seventh Annual Meeting of the British Association of Urological Surgeons in London, June 1971.

9

10 B R I T I S H J O U R N A L OF U R O L O G Y

RENAL FAILURE

1155 Caras (3,6 par cant)

Fig. I.-Total number of pat- ients admitted during the last 1 1 years (1960-1970) compared with the number of renal failure

cases. Fig. 2.-Number or patients

with obstructive urxmin. Fig. 3.-calculous anuria: 80

cases.

Retroperitoneal malignant fibrosis 4 cares Neuroganic bladder 5

Renal tumours 8 Mal format ions- 9

Polycystic kidneys 22 Rena l tuberculosis - 2 4

Carc inoma 01 cerv ix -39

Acute pyelonephritis 44 - Nephrolithiarir - 108

b Bladder tumours 127

Prostatic hypertrophy t Malignancy 188 r

FIG. 3

ERRORS A N D PITFALLS I N ACUTE U R I N A R Y O B S T R U C T I O N 1 1

Our policy in these cases consisted of: 1 . If the patient was admitted in good condition with mild uramia and was a good operative

risk, the urinary obstruction was relieved forthwith by surgical removal of the calculus provided the site of obstruction was known beforehand, e.g. by the stone being radio-opaque.

Whenever the renal calyces were grossly dilated and/or the urine was infected, the surgical procedure concluded with a temporary drainage procedure-nephrostomy when the kidney was in the operative field, or ureterostomy in situ. When the stone was radiolucent and/or could not be located on the plain film, the site of obstruction was determined by ureteric catheterisation and the surgical approach selected accordingly.

2. If the patient was admitted with severe urzmic intoxication, we usually tried to restore the urinary flow by means of ureteric catheterisation. If this attempt failed, a temporary drainage procedure, usually nephrostomy-under local anasthesia if necessary-was performed.

A number of patients were operated on after initial haemodialysis. Our results are presented i n Table 1.

TABLE I Calculous Anuria: Results in 80 Patients

PROCEDURE

Haemodialysis

-~ _ _ _ _

~- ~~~

Elimination

18 died 23 per cent ] TOTAL NUMBER 80 CASES :

d = died 62 cured [ 77 per cent I c = cured

12 B R I T I S H J O U R N A L O F U R O L O G Y

Except for some indisputable successes, this policy was subject to pitfalls and errors which will be analysed later.

Ureteric Cutheteris.ution.-This was used in 37 patients either alone (19 cases-I 7 relieved. 2 died), or in combination with hzmodialysis (2 cases-both relieved) or with surgery ( 1 6 cases- 12 relieved, 4 died).

Undoubtedly for a quick and easy relief of urinary obstruction this procedure may be of' great value. However, the following unsatisfactory situations may arise:

( N ) The ureteric catheter may fail to pass beyond the site of obstruction, yet surgical relief is illogically postponed and on the days following other attempts at ureteric catheterisation are made which may favour ascending infection and renal deterioration.

( b ) The ureteric catheter does succeed in relieving the obstruction but is niaintaincd indwell- ing for too long. Urinary infection is consequently almost unavoidable, sometimes taking the form of acute pyelonephritis, with recurrence of the urzmia.

I n our series 8 patients had longlasting pyelonephritis after ureteric catheterisation, despite the fact that they subsequently eliminated the calculus.

(c) The ureteric catheter may give false information concerning the site of obstruction i n the case of a non-opaque stone. For example, it may be arrested in the lower segment of the ureter, when the stone is actually impacted in the uretero-pelvic junction thus leading to an unsuitable approach.

In 3 of our cases we erroneously opened the abdominal wall through Key's subumbilical midline incision when the stones were located in the upper ureter.

(cl) The improvement brought about by ureteric catheterisation is easily reversed ; the catheter may become obstructed and the anuria recur when the catheter is removed.

I n 16 of our cases we were forced to remove a blocked catheter and to resort to surgery. Siirgery.-Fifty-two patients underwent open surgical procedures. In 26 cases the surgical

procedure was performed as an emergency (5 died), in 10 cases surgery was associated with hzmo- dialysis (5 died), and 16 patients had an indwelling ureteric catheter before surgery (4 died).

The mortality rate in this group was 25 per cent (13 patients).

TABLE I1 Calculous Anuria-Surgical Treatment and Results in 52 Patients

I __-- I

I Number of Technical Procedure Cases

~ ~ ~ ~ _ _ _ - ~ ~ - - _ _ _ _ - ~ U reteroli t hot only . In sitrr ureterostomy . Pyelolithotomy . . Pyelolithotomy +Pyelostomy . Nephrostomy . Nephrolithotorny +Nephrostomy . Pyeloplasty .

-. -~~

25 2 8 3

10 3 1

i Numhcr of 1 Surgery +Dialysis Dcceascd Caws Number of Cases:

4

... I 2 ...

~ ________ ~ -~

I I

4 ... 6 1 ..I I

~

In Table I1 the procedures and results are shown. Undoubtedly surgery has a higher risk when performed on a urzmic patient, but it may be

life-saving when properly indicated and executed. The greatest error one can make in this respect is not to operate on a patient i n a well-

tolerated clinical phase of urzmia and either to waste time waiting for spontaneous elimination of a ureteric calculus or to rely too much on the ureteric catheter. The consequences of postponing

E R R O R S A N D P I T F A L L S I N A C U T E U R I N A R Y O B S T R U C T I O N 13 surgery may be having to undertake a more hazardous procedure on a patient in a much poorer condition. Of the 18 patients who died, 16 were in the group with severe uramia.

Another surgical error consists of performing surgery in good time, but ending the operation without providing proper relief of urinary obstruction.

Three patients were referred for hamodialysis with grossly distended kidneys and acute pyelonephritis because at a previous operation neither had the obstructive calculus been removed nor had tube drainage been instituted. Nephrostomy and dialysis were carried out but all died i n bacteramic shock.

A difficult problem is presented by those uramic patients whose calculi on radiography do not seem to be definitely obstructing the urinary tract. Our impression is that operative procedures are rarely indicated in such cases which belong rather to the province of the nephrologist. The ureteric catheter may be most valuable in identifying these cases; if ureteric catheter drainage does not improve the urinary drainage, surgery will be of no avail.

The unwary surgeon may, however, be tempted to do a radical but time-consuming and dangerous operation instead of performing a quick and less aggressive one. We regret performing a pyeloplasty instead of a life-saving nephrostomy in a patient with acute pelvi-ureteric obstruction in a solitary kidney with uramia which had been temporarily controlled by hamodialysis.

Bilateral Obstructive Nephrolithiasis and Advanced Ur=mia.- Out of a total of 304 patients with bilateral nephrolithiasis, 196 had a normal blood urea; in 85 cases it was higher than 70 mg per 100 ml. and 23 patients were admitted with advanced uramia with the blood urea higher than 100 mg. per 100 ml. and with the creatinine clearance below 40 ml. per minute (Table 111).

TABLE 111

Bilateral Obstructive Nephrolithiasis and Urremia Normal blood urea . . 196 cases

, 23 cases Blood urea 70 mg. per 100 ml. Blood urea 100 mg. per 100 ml.

304 cases

.

.

Only the 23 severely uramic patients will be analysed here. All of them had bilateral multiple kidney stones and a clinical course extending over many

years. As long as their kidney function tests remained normal surgery had been deemed unnecess- ary and as soon as they became uramic surgery had been considered both useless and risky.

For many years such patients had been abandoned to an apparently unavoidable death. However, the advent of hremodialysis has given rise to new hope and has obliged us to change our attitude.

In the group of 23, 8 patients were treated conservatively; 7 died and only 1 was improved by hEmodialysis alone.

The other 15 patients were operated upon under the protection of hamodialysis. This resulted in surprisingly good and lasting benefit in 7, but the remaining 8 died.

Nevertheless, these results may be considered as a convincing plea for a more active surgical approach in bilateral renal lithiasis complicated by uramia.

Since hremodialysis can turn a very poor risk patient into an acceptable one and lower the post-operative mortality, renal insufficiency can no longer be considered as a contra-indication to operation for bilateral renal lithiasis. In fact, surgery performed with certain precautions and under the protection of dialysis is the essential factor in the recovery of renal function. One should not forget that in such cases potentially reversible renal lesions almost always exist and the renal parenchyma has surprising resources of recovery, provided that the obstruction is relieved and the infection is controlled.

14 BRITISH J O U R N A L OF U R O L O G Y

SUMMARY

Six hundred and fifty-four patients with obstructive uramia are reviewed,with special emphasis on calculous anuria and bilateral nephrolithiasis complicated by blood nitrogen retention.

Some errors and pitfalls in the management of acute obstructive uramia are discussed, followed by a brief analysis of the results obtained in the treatment of bilateral kidney stones and renal failure.

Such cases should no longer be abandoned, because surgery performed under protection of hxmodialysis can often provide unexpectedly good results.

REFERENCES

CHISHOLM, G. D. and SHACKMAN, R. (1968). Malignant obstructive uraemia. Eritish Jorrrrral o/'

EAKLAM, R. J. ( I 967). Recovery of renal function after prolonged ureteric obstruction. Eritish Journal of Urology, 39, 58-62.

Fox, M. and PARSONS, F. M. (1964). Indications for haemodialysis in advanced uraemic prostatic obstruction. British Jorrrnal of Urology, 36, 487-492.

MURNAGHAN, G. F., WILLIAMS, H. B. L. and JEREMY, D. (1965). Urological survey of chronic pyelonephritis and recurrent urinary infection without obstruction. Erifish Jorrnzal of Urolc>,rj,.

On the treatment of bilateral nephrolithiasis associated with chronic renal

U r o l ~ g . ~ , 40, 720-726.

37, 79-87. PROCA, E. (1970).

insufficiency. Chirrtrgia (Errcharest), 19, 61 7-630.

DISCUSSION

Sir Eric Riches (London) favoured nephrostomy as a preliminary to surgical correction and referred to a patient aged 26 in Pakistan treated in 1957 when no dialysis was available. He had anuria with a blood urea of 220 mg. per cent from gross bilateral hydronephrosis. Right nephro- stomy had enabled him to come to England where bilateral plastic operations were done. The kidneys remained enlarged and infected but he was working and leading a normal life 14 years later; the blood urea in 1971 was 40 mg. per cent.